bridge.lists.linux.dev archive mirror
 help / color / mirror / Atom feed
From: Lane Brooks <lane@brooks.nu>
To: bridge@osdl.org
Subject: [Bridge] MTU confusion
Date: Tue, 06 Sep 2011 18:25:16 -0600	[thread overview]
Message-ID: <4E66B9EC.8050603@brooks.nu> (raw)

I am confused regarding MTU issues and bridging.

I have setup an bridge with an MTU of 1492 for the bridge and all the 
devices in the bridge.

I setup the device interface on one leg of the bridge to have an MTU of 
1492 as well. I mount an nfs share on another leg of the bridge. This 
device has an MTU of 1500 and I get problems with the nfs mount until I 
set the MTU to 1492. Do I have to set all devices on the bridge to have 
an MTU of 1492 for the bridge to work? The reason I am confused is that 
the if the two devices are connected directly with one having an MTU of 
1492 and the other 1500, things work. However, putting the bridge 
between them requires setting both devices to have an MTU of 1492.

Here is the bridge setup:


root@bug20:~# brctl show br0
bridge name     bridge id               STP enabled     interfaces
br0             8000.0050c269c63f       no              eth0
                                                         usb0
root@bug20:~# ifconfig -a
br0       Link encap:Ethernet  HWaddr 00:50:C2:69:C6:3F
           inet addr:192.168.75.133  Bcast:192.168.75.255  
Mask:255.255.255.0
           inet6 addr: fe80::250:c2ff:fe69:c63f/64 Scope:Link
           UP BROADCAST RUNNING MULTICAST  MTU:1492  Metric:1
           RX packets:128521 errors:0 dropped:0 overruns:0 frame:0
           TX packets:45471 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:0
           RX bytes:163191890 (155.6 MiB)  TX bytes:39435311 (37.6 MiB)

eth0      Link encap:Ethernet  HWaddr 00:50:C2:69:C6:3F
           UP BROADCAST RUNNING MULTICAST  MTU:1492  Metric:1
           RX packets:44140 errors:0 dropped:0 overruns:0 frame:0
           TX packets:60299 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:1000
           RX bytes:16728060 (15.9 MiB)  TX bytes:79965979 (76.2 MiB)

usb0      Link encap:Ethernet  HWaddr D2:D0:1C:9A:35:8F
           inet6 addr: fe80::d0d0:1cff:fe9a:358f/64 Scope:Link
           UP BROADCAST RUNNING MULTICAST  MTU:1492  Metric:1
           RX packets:13914 errors:0 dropped:0 overruns:0 frame:0
           TX packets:7373 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:1000
           RX bytes:20359268 (19.4 MiB)  TX bytes:778806 (760.5 KiB)



Thanks,
Lane

                 reply	other threads:[~2011-09-07  0:25 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4E66B9EC.8050603@brooks.nu \
    --to=lane@brooks.nu \
    --cc=bridge@osdl.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).